Find the missing term in the series: 5, 6, 11, 17, 28, ...

Solution: Find the pattern by looking at differences between consecutive terms.

1. Compute differences: 6 − 5 = 1, 11 − 6 = 5, 17 − 11 = 6, 28 − 17 = 11. So the differences are 1, 5, 6, 11.

2. Observe the recurrence: from the third difference onward each difference equals the sum of the two previous differences (6 = 1 + 5, 11 = 5 + 6).

3. Compute the next difference: 6 + 11 = 17.

4. Add this to the last term: 28 + 17 = 45.

Answer: 45